Tunnelling shield

ABSTRACT

A tunnelling shield provided with shock absorbing supports in the form of hydraulic jacks which via freely rotating rollers are in constant contact with the periphery of the back side of the rotary rock-cutting member.

United States Patent [151 3,695,720 Bolotin et al. [45] Oct. 3, 1972 [54] TUNNELLING SHIELD [21] Appl. No.: 66,033 [72] Inventors: Evgeny Moiseevich Bolotin,

Otkrywe Shossc, korpus [52] us. Cl ..299/33, 299/56 Boris Nikolaevich ms y, [51] Int. Cl ..Elg 3/04 t yt ho o p -a, W [58] Field of Search ..299/31, 33, 90 Igor Semenovich Ostrovsky, Otkrytoe shosse, 24, korpus 31, kv. [56] Refer nces Cited 21; Vladimir Ivanovich Razmerov, Leningradskoe shosse, 62, kv. 90; UNITED STATES PATENTS Valenti" R", Studeni 3 511,539 5/1970 Schonfeld ..299/ x sky Proezd, 6, 12; Mlkhall 3,325,217 6/1967 Enz .299/31 seevich Rivilis, Otkrytoe shosse, 24, korpus 32, kv. 4; Leonid Ivanovich Saveliev, Otkrytoe shosse, 29, korpus ll, kv. 58; Leonid Konstantinovich Khaidurov, Otkrytoe shosse, 24, korpus 5-g, kv. 31', Vladimir Alexandrovich Khodosh, ulitsa Burdenko, l6, kv. l6; Nikolai Dmitrievich Pisarev, Otkrytoe shosse, 24, korpus 5-a, kv. 20, all of Primary Examiner-Ernest R. Purser Attorney-Waters, Roditi, Schwartz and Nissen [57] ABSTRACT A tunnelling shield provided with shock absorbing supports in the form of hydraulic jacks which via freely rotating rollers are in constant contact with the periphery of the back side of the rotary rock-cutting Moscow, USSR. member.

[22] Filed: Aug. 21, 1970 9 Claims, 4 Drawing Figures 6 l7 l6 a 72 D Z 3 l5 70 g 76 I3 PATENTEDUBTB I972 3,695.7 20

SHEET 2 OF 2 TUNNELLING SHIELD The present invention relates to tunnelling shields employed for constructing tunnels of various types.

Tunnelling shields are widely known and, as a rule, comprise a body with feed jacks, said body accommodating a movable frame which carries a rotary rockcutting member.

It is known that the ground cut during tunnelling often includes stretches with varying hardness of rock across the tunnel face or stretches of brocken rock or else with partial face fall. Therefore, when shields are used under such conditions, the front of the rockcutting member is subjected to heavy and irregular loads which cause cocking of the rotor and, sometimes, its deformation. This becomes most conspicuous in the case of large-diameter shields.

To resist the irregular loads acting on the rockcutting member, the latter has to be made robust which, increases its weight and impairs its operation.

The present invention is intended provide a tunnelling shield to eliminate the aforesaid disadvantages.

The object of the invention is to provide an improved tunnelling shield which insures uniform distribution of loads acting on the rock-cutting member.

The object is accomplished by a tunnelling shield whose body accommodates a frame carrying the rotary rock-cutting member. In accordance with the invention, installed in the body are hydraulic jacks which mount freely rotating rollers in constant contact with the periphery of the back portion of the rock-cutting member via said rollers and which function as shock absorbing power supports.

- The invention is also characterized in that the rollers are secured on the jack plungers and the latter are kept in the extreme extended position thereby creating a shock absorbing support, and in that the working spaces of these jacks are in communication with a source of fluid pressure through a common pressure line provided with a safety valve.

The arrangement of the shock absorbing supports in the form of hydraulic jacks around the periphery of the rock-cutting member eliminates cocking of the latter and provides for a uniform distribution of loads over its front portion.

Now the invention will be described in detail by way of example with reference to the appended drawings, in which:

FIG. 1 is a longitudinal section of the tunnelling shield according to the invention, wherein the shock absorbing supports (hydraulic jacks) are secured on the frame which mounts the rock-cutting member;

F IG. 2 is a section taken along line II-II in FIG. 1;

FIG. 3 is a longitudinal section on enlarged scale of the hydraulic jack with a roller and the fastening of the jack to the shield frame;

FIG. 4 is a diagrammatic illustration of the hydraulic system of the jacks.

Secured in shield body 1 (FIGS. 1 and 2) are horizontal guides 2 on which frame 3 is installed, the latter carrying a rotary rock-cutting member 4. For this purpose, the frame 3 is provided with a bearing 5, located in which is axle 7 of the rock-cutting member 4, said axle being fastened with a nut 6; the frame is also provided with rollers 8 resting on which is circular raceway 9 of the rock-cutting member 4.

The rock-cutting member 4 is rotated by drives 10 installed on the frame 3 via gear or pin wheel 11 secured on the circular raceway 9. Depending on the hardness and stability of the rocks being cut, the rockcutting member 4 can be extended from the shield body 1 by different distances by means of hydraulic cylinders 12 which displace the frame 3 on the guides 2 and feed the rock-cutting member 4 against the face of the tunnel.

The working feed of the shield body 1 towards the rock face is efi'ected by the hydraulic jacks I3 bearing against the tunnel lining (not shown), the latter being laid in the form of tubing rings or blocks with the aid of erector 14 of a conventional design, installed in the rear end of the shield body 1.

The rock broken down by the rock-cutting member 4 is loaded on a conveyer 15 into a transport vehicle (not shown).

As has already been stated above, the subject-matter of present invention lies in the provision of the shock absorbing power supports in the form of hydraulic jacks 16, carrying freely rotating rollers 17 in constant contact with the periphery of the back side of the rockcutting member 4.

As is shown in FIG. 3, the bodies 18 of the jacks 16 are installed on the frame 3 with capability of longitudinal adjustment with the aid of adjusting screw 19, secured on the face of the body 18 and extending through threaded hole 20 in bracket 21 of the frame 3.

The jacks 16 are moved by the screws 19 until the rollers 17 come into contact with the back side of the rock-cutting member 4, whereupon they are fixed by said screws 19 in this position. It is necessary after the rollers 17 have come into contact with the rock-cutting member, that the plungers 22 of the jacks 16 holding said rollers should be extended to the extreme position relative to the bodies 18. This is required for ensuring a constant contact between the rollers 17 and the back side of the rock-cutting member 4 and for obtaining the shock absorbing and power effect.

The working spaces 23 of the jacks 16 are intercommunicated by common pressure line 24 (FIG. 4) connected to a source of fluid pressure (not shown). The pressure line 24 is provided with safety valve 25 which ensures by-passing of the fluid from the working spaces 23 of the jacks 16 through line 26 as soon as the fluid pressure therein exceeds the rated limit.

In the course of the shield operation, the load applied to the rack-cutting member 4 is transmitted to the frame 3 by the bearing 5 and the hydraulic jacks 16 which create a constant resisting force along the periphery of the back side of the rock-cutting member 4. Thus, the jacks l6 prevent the rock-cutting member 4 from cocking, and contribute to a more uniform distribution of the load acting on it in the course of operation.

The present invention simplifies the design of the shield, and makes it possible to decrease its weight and improve its efiiciency, particularly when constructing large-diameter tunnels.

The operating principle of the shield according to the invention is analogous to that of the known shields and can be briefly stated as follows.

The rotating rock-cutting member 4 is fed together with the frame 3 towards the face by the power cylinders 12; when one cutting operation is completed, the frame 3 with the rock-cutting member 4 is returned to the initial position by the same cylinders 12, while the shield body 1 is moved towards the face by the jacks 13. Then, the process is repeated in the same sequence. As it has already mentioned, the tunnel lining elements are assembled by the erector 14 after the forward movement of the shield body 1.

What is claimed is:

l. A tunnelling shield comprising an annular shield body, a frame disposed within said shield body, means slidably supporting said frame on said shield body for axial displacement with respect thereto, first jack means coupled to said frame and shield body and extending axially to effect relative axial displacement between said frame and shield body and to hold the same in a given relative axial position, second jack means connected to aid shield body to move the same axially within a tunnel towards a face thereof to be cut or away therefrom, an annular rock cutting member rotatably mounted in said frame and projecting forwardly thereof, means for rotating said rock cutting member in said frame, third jack means disposed within said shield body and connected axially between said frame and said rock cutting member, said third jack means including a plurality of jacks arranged around the axis of rotation of the rock cutting member, and freely rotatable rollers carried by said jacks and urged into constant contact with the rock cutting member at the periphery of the back surface thereof so that the jacks serve as shock absorbing supports for the rock cutting member with respect to the frame.

2. A shield as claimed in claim 1 wherein said means for rotating the rock cutting member comprises a drive means including a drive wheel, said rock cutting member including an inner peripheral gear in mesh with said drive wheel.

3. A shield as claimed in claim 2 wherein said drive means includes a plurality of said drive wheels arranged annularly along the inner peripheral gear of the rock cutting member.

4. A shield as claimed in claim 1 wherein said jacks are arranged symmetrically around said axis of rotation of the rock cutting member.

5. A shield as claimed in claim 4 wherein said jacks are arranged in an annular array around said axis of rotation of the rock cutting member.

6. A shield as claimed in claim 5 comprising support rollers peripherally mounted on said frame and internally engaging said rock cutting member to rotatably support the same.

7. A shield as claimed in claim 6 comprising a common hydraulic line connected to all of said jacks, and a safety valve in said line.

8. A shield as claimed in claim 7 wherein said jacks each includes a plunger which is displaceable between retracted and extended positions, said plungers being in fully extended positions during a cutting operation, said jacks all being pressurized from said common hydraulic line.

9. A shield as claimed in claim 8 wherein said jacks each includes a body containing said plunger, and means for fixedly adjusting the position of said body with respect to said frame. 

1. A tunnelling shield comprising an annular shield body, a frame disposed within said shield body, means slidably supporting said frame on said shield body for axial displacement with respect thereto, first jack means coupled to said frame and shield body and extending axially to effect relative axial displacement between said frame and shield body and to hold the same in a given relative axial position, second jack means connected to aid shield body to move the same axially within a tunnel towards a face thereof to be cut or away therefrom, an annular rock cutting member rotatably mounted in said frame and projecting forwardly thereof, means for rotating said rock cutting member in said frame, third jack means disposed within said shield body and connected axially between said frame and said rock cutting member, said third jack means including a plurality of jacks arranged around the axis of rotation of the rock cutting member, and freely rotatable rollers carried by said jacks and urged into constant contact with the rock cutting member at the periphery of the back surface thereof so that the jacks serve as shock absorbing supports for the rock cutting member with respect to the frame.
 2. A shield as claimed in claim 1 wherein said means for rotating the rock cutting member comprises a drive means including a drive wheel, said rock cutting member including an inner peripheral gear in mesh with said drive wheel.
 3. A shield as claimed in claim 2 wherein said drive means includes a plurality of said drive wheels arranged annularly along the inner peripheral gear of the rock cutting member.
 4. A shield as claimed in claim 1 wherein said jacks are arranged symmetrically around said axis of rotation of the rock cutting member.
 5. A shield as claimed in claim 4 wherein said jacks are arranged in an annular array around said axis of rotation of the rock cutting member.
 6. A shield as claimed in claim 5 comprising support rollers peripherally mounted on said frame and internally engaging said rock cutting member to rotatably support the same.
 7. A shield as claimed in claim 6 comprising a common hydraulic line connected to all of said jacks, and a safety valve in said line.
 8. A shield as claimed in claim 7 wherein said jacks each includes a plunger which is displaceable between retracted and extended positions, said plungers being in fully extended positions during a cutting operation, said jacks all being pressurized from said common hydraulic line.
 9. A shield as claimed in claim 8 wherein said jacks each includes a body containing said plunger, and means for fixedly adjusting the position of said body with respect to said frame. 